Coaxial cross-point relay



June 27, 1967 c. VAN I OO 3,328,547

COAXIAL CROSS-POINT RELAY Filed Feb. 2. 1965 2 Sheets-Sheet 1 nn l Il am74 78 JJ 22 S INVENTOR..

COENRAAD VAN LOO Wgm June 27, 1967 C. VAN L00 3,328,547

COAXIAL .CROSSPOINT RELAY Filed Feb. 2, 1965 2 Sheets-Sheet 2 INVENTOR.COENRAAD VAN `L00 BYWQM United States Patent O 3,328,547 COAXIALCROSS-POINT RELAY Coenraad Van Loo, San `lose, Calif., assigner toJennings Radio Manufacturing Corporation, San Jose, Calif., acorporation of Delaware Filed Feb. 2, 1965, Ser. No. 429,855 14 Claims.(Cl. 20G-153) This invention relates to coaxial relays, and particularto a vacuum coaxial cross-point relay.

Cross-point matrices are useful in the communication arts to connect asingle receiving or transmitting station with one or more receiving ortransmitting antennae. It has been the practice in conventional matricesto utilize a plurality of separate individually controlled relays toaccomplish this function. This has resulted in space-consumingcomplicated arrays such as that disclosed in the United States PatentNumber 2,938,999 issued to William A. Etter on May 3l, 1960, and in thenecessity of an unwieldy control circuit to control the multiplicity ofrelays incorporated in such matrices. It also results in needlessexpense and multiplication of parts. It is therefore one of theprincipal objects of the present invention to provide a selectivity andversatility in cross-point switching not heretofore available With knowncross-point relays.

One of the disadvantages of conventional coaxial relays hase been theexistence of undesirable inductive capacitance resulting in cross-talkbetween adjacent circuits. This problem is a difficult one becausesolutions to this problem usually create other undesirable problems suchas difficulty of fabrication or disruption of the voltage standing waveratio (VSWR). Accordingly, another principal object of the invention isto provide a crosspoint type coaxial relay designed to eliminate crosstalk between adjacent circuits while providing a low voltage standingWave ratio in the order of 111.085.

Another disadvantage found in conventional vacuum coaxial relays is theabsence of characteristics which render such relays suitable 4foroperation over a wide band of the frequency spectrum. It is therefore astill further object of the invention to provide a cross-point typevacuum coaxial relay suitable for wide band operation in the frequencyrange, say, from to 600 megacycles at power ratings up to 5 kilowatts.

Because communication installations are expensive in terms of time andmaterials, there is great reluctance to modify an existing system toincorporate new components unless such new components fit int-o theframework of cost and function originally planned for the installation.Any new device, such as a new, vacuum coaxial relay, is required to fitconveniently into the original concept of design of the system andassociated equipment which the systems manufacturer already hasoperating in the field, or which it is presently designing for futureinstallation. Accordingly, it is -a still further object of theinvention to provide a coaxial relay of the cross-point type which willreadily accommodate standard coaxial connectors, or a combinationthereof, to render the relay compatible with existing systems.

Coaxial ymatrices of conventional design have heretofore utilizeddevices such as relays and connecting hardware which rendered suchmatrices voluminous and heavy, thus precluding or restricting their usein airborne equipment where space and weight are important factors. Itis therefore another object of the invention to provide a vacuum coaxialrelay of the two-pole, two-position cross-point type which is compact inconfiguration, low in weight, and which is provided with standardcoaxial fittings in a manner to minimize the space requirements of amatrix in which it is incorporated.

The economical manufacture or reliable vacuum electronic components ofany type is a difficult task, principalice ly because the design of suchcomponents requires skilled mechanical and electronic engineers capableof producing a component design that can be mass-produced and stillperform the intended functions. Additionally the manufacturer of vacuumdevices `requires considerable quality control and careful handling ofthe parts prior to their assembly, and considerable care in thenecessary processing and testing of each device after it has beenassembled. Accordingly, it is a still further object of the invention toprovide a vacuum coaxial relay which is made up from parts which may beaccurately fabricated and expeditiously assembled into a composite wholeby mass production techniques.

The invention processes other -objects and features of advantage, someof which, with the foregoing, will be apparent from the followingdescription and drawings. It is to be understood, however, that theinvention is not limited to the embodiment illustrated and described, asit may be embodied in various forms within the scope of the appendedclaims.

Referring to the drawings:

FIG. l is a vertical cross-sectional view taken in the plane indicatedby the line 1-1 in FIG. 2.

FIG. 2 is an elevation taken in the direction indicated by the arrow 2in FIG. l.

FIG. 3 is a plan view of the fixed contact support plate shown apartfrom the remaining portion of the relay.

FIG. 4 is a perspective view, with the fixed contact support plateremoved to disclose the underlying mobile contact assembly. The viewillustrates the relationship Abetween the fixed contacts and the mobilecontact assembly.

Broadly considered, the coaxial cross-point relay of the inventioncomprises an evacuated metallic envelope including at one end acup-shaped shell member having around its open periphery a radiallyoutwardly extending flange. This cup-shaped end member insulatedlysupports a plurality of conductors terminating within the envelope infixed contact points, selected ones of which are adapted to be engagedand disengaged by a movable contact assembly. The other end of theenvelope is closed by a generally conically-shaped metallic shell,having a radially outwardly extending peripheral fiange abutting thefiange of the opposing cup-shaped end member, and also supporting anactuator mechanism extending axially into the envelope and supportingthe movable contact assembly. Means are provided interposed between thetwo cupshaped shells constituting the envelope to effect their alignmentprior to final seal, and also to function as a ground plane to whichselected ones of the movable contacts may be abutted. Coaxial connectorsare detachably mounted on the first mentioned relatively shallowcupshaped shell member in a manner to engage the tubular conductorswhich terminate in the contact points. The manner of connection of thecoaxial connectors is such as to insure that the transition from an airdielectric to a vacuum dielectric does not result in reflection of theradio signal or an abrupt change in the voltage standing wave ratio.Means are also provided within the envelope constituting ground planesagainst which selected sets of movable contact blades may abut when theswitch is actuated.

In terms of greater detail, the vacuum coaxial crosspoint relay of theinvention comprises an evacuated metallic envelope designated generallyby the numeral 2, including a relatively shallow metallic cup-shapedshell 3, formed from a base plate 4 having a peripheral cylindricalflange 6, thereabout as shown best in FIG.l. The cylindrical fiange 6 isprovided with a radially outwardly extending seal flange 7. The baseplate 4 is provided with a plurality of radially and circumferentiallyspaced apertures 8, each of the apertures 8 being provided with achamfer which results in a thin edge portion 9 as shown in FIG. 1, andto which the ange member 12 of tubular dielectric member 13 ishermetically brazed.

Extending through and hermetically brazed within the tubular dielectricmembers 13 extending through the apertures 8 are tubular conductors, 14,16, 17 and 18, terminating within the envelope in radially inwardlyextending contact points 19, 21, 22 and respectively, 23, as shown bestin FIGS. 3 and 4. Each of the tubular conductors 14, 16, 17 and 18 isadapted to be connected conductively by the pin connectors 24 carried byconventional coaxial fittings 26, 27, 28 and 29 shown best in FIGS. 1and 2. These latter are detachably secured to a mounting plate 31, whichis in turn detachably secured to a support plate 32, brazed to the endplate 4 of the envelope. The plate 31 at the occurrence of each of theconventional coaxial couplings is bored to provide an aperture 33 havinga diameter gauged to cooperate with the diameter of the dielectricmember 13 to provide a smooth transition from the air dielectric withinaperture 33 to the vacuum dielectric within the envelope.

Attachment of the conventional coaxial couplings to the base plate 31 isaccomplished by screws 34 as shown. Attached to the inner side of endwall 4 opposite the plate v32 is a tubular shell 36 having a radiallyinwardly extending ange 37 and forming a ground plane against whichelements of the mobile contact assembly may abut during operation of theswitch. The aperture defined by the flange 37 is preferably rectangularas shown best in FIG. 3, with the corners of the rectangular aperturebeing in line with -opposed fixed :contacts 16-23 and 19-22. The tubularmember 36 thus cooperates with other structure to be subsequentlydescribed to insure that the impedance through the switch remainssubstantially the same as the impedance through the transmission line.

Closing the open end of the cup-shaped 3, is a second cup-shaped member38 having a conical section 39 which merges into a radially extendingflat shoulder portion 41,which in turn is integral with a cylindricallyextending fiange portion 4t2, provided at its outer peripheral edge witha radially outwardly extending fiange 43 adapted to be heliarc welded tothe flange 7 on cupshaped member 3. At its other end, the cup-shapedmember 38 is provided with a cylindrically extending portion 44 mergingwith a radically inwardly extending portion 47. Within theflange portion47 is heliarc welded the outer open end 48 lof an expansible `metallicbellow 49, the inner end of which is heliarc welded to a tubular fiangeS1 having one end thereof brazed as at 52 about the actuator shaft 53adjacent its inner end. The outer end of the actuator shaft 53 isprovided with a threaded section 54, while the ,inner end of the shaft53 is provided with a reduced in diameter` portion S6.

On the inner end of the actuator shaft is supported a mobile contactassembly including a cruciform dielectric support plate 62, arrangedperpendicularly withl respect to the axis of the actuator shaft. Thedielectric support plate 62 has appreciable thickness, in order of about3/16 of an inch, and is shown best in FIGS. l and 4. Adjacent the endsof each pair of its cruciform arms, but on opposite surfaces onperpendicularly disposed pairs of arms, are brazed two pairs ofconductive resilient contact blades 63 and 64. As shown best in FIGS. 1and 4, the blades of the pair of contact blades 63 are spaced apart onopposite sides of the axis of the actuator shaft and are brazed in theright hand surface of the dielectric member 62. Each blade of the pairincludes a central portion 66 brazed to the end of the associated arm ofthe cruciform dielectric member, and laterally extending thin reslientmetallic finger portions 67 and 68 extending in opposite directionsperpendicular to the arm on which it is attached and as shown best inFIGS. l and 2.

The resilient contact blades 64 are likewise spaced apart on oppositesides of the axis of the actuator shaft but are supported on theopposite side of the cruciform dielectric member 62 from the blades 63.Each of these contact blades is provided with a central body portion 68,which overlaps and is brazed to the end portion of the associated arm ofthe cruciform vdielectric support member, and with laterally extendingthin resilient metallic finger portions 69 and 71 extending in oppositedirections perpendicular to the arms on which it is attached as shownbest in FIGS. 1 and.4.The mobile -contact assembly is secured to theactuator shaft by a grommet 72 brazed to the reduced-in-diameter portion56 of the shaft as shown best in FIG. l.

It will thus be seen that the mobile contact assembly is spaced withrespect to fixed contact points 19, 21, 22 and 23 so that one pair ofthe resilient contact blades 63 and 64 are positioned on one side of thefixed contact points and the other pair of contact blades 63 or 64v arepositioned on the opposite side of the fixed contact points.Accordingly, when the actuator shaft isk displaced in an axial directionby any appropriate means (not shown), the mobile contact assembly movesfrom left to right and back again so as to bring first one pair ofcontact blades, such as 63, into contact with 2 selected pairs of thefixed contact points, while when the mobile contact assembly is moved inthe opposite direction, i.e., toward the support plate 4, the Contactblades 64 are brought into conductive contact with a different set ofytwo selected pairs of fixed contact points.

Thus, as seen in FIG. l, expansion by the bellows by atmosphericpressure will effect engagement and interconnection of the fixedcontacts 19 and 23 by one of the contact blades 64 to complete a circuittherethrough, while the fixed contact points 21 and 22 will be engagedand interconnected by the opposite contact blade 64 of the same pair. Onthe other hand, when the actuator of the switch is energized, as by asolenoid, or by hand, to overcome atmospheric pressure and thus collapsethe bellows to displace the pair of mobile contact blades 63 to the leftas viewed in FIG. 1, the pair of resilient contact blades 63 willconductively conne-ct fixed contact point 19 to fixed contact point 21,and fixed contact point 22 to fixed contact point 23. It willaccordingly be seen that a cross-point connection has been effectedbetween the enumerated fixed contact points.

In order to yeliminate crosstalk `between the pairs of contact pointsand pairs of circuits that are open condition, shield means are providedwithin the envelope interposed between the resilient contact blades 63and 64 in a manner to effect shielding of these contact blades from each-other by providing a ground plane disposed therebetween. This isaccomplished by providing a hollow metallic shell-like ground likemember 73, shown best in FIG. 1, and comprised of an annular plateportion 74, having a cylindrical flange portion 76 extending parallel tothe cylindrical portions 6 and 42 of shells 3 and- 38, respectively, andextending across the joint between flanges 7 and 43 on the cup-shapedenvelope portions. It will thus be seen that the cylindical portion 76of the cup-shaped members 74 functions to align the cup-shaped member 3with the cup-shaped member 38. The member 74 is preferably brazed withinthe corner formed between the radially outwardly extending portion 41and the cylindrical tiange portion 42 of cup-shaped housing or envelopemember 38. vThe radially inwardly extending portion of the member 74adjacent in its periphery, is utilized to support a plurality ofradially extending thin metallic members 77, a portion of each of whichextends into the corner between adjacent arms of the cruciformdielectric member 62. This outwardly extending portion of the member 77extends through the aperture in plate 74, while a Harige portion 78extends radially outwardly along the underside of the plate 74 and isbrazed thereto. It will thus be seen that when the actuator is activatedto move the shaft 53 to the left as viewed in FIG. 1, the mobile contactblades 64 on the left-hand side of the dielectric cruciform member 62,come into grounding contact with the bottom plate portion of thecup-shaped member 74. On the other hand, when the actuator is activatedby atmospheric pressure working on the inside of the bellows, theContact blades 63 move to the right as viewed in FIG. 1 and come intoconductive contact with the ground plane or shell 36. It will thus beapparent that each of the pairs of mobile contact blades which are notin circuit are grounded to the metallic envelope. It should also beapparent that the projecting portions of plates 77 which project intothe corners between adjacent cruciform arms suitably shield the two opencircuits through the switch.

I claim:

1. A coaxial cross-point relay comprising an envelope including acup-shaped actuator support shell and a cupshaped fixed-contact supportshell hermetically united to the actuator support shell, each of saidcup-shaped shells having a bottom and a cylindrical side wall, aplurality of spaced conductors extending insulatedly and hermeticallythrough the bottom of said fixed-contact support shell and terminatingwithin the envelope in a plurality of spaced fixed contact points, amobile contact assembly disposed within the envelope and including pairsof resilient contact blades arranged to conductively connect a pluralityof pairs of said fixed contact points when the mobile contact assemblyis moved in one ydirection and to conductively lconnect a plurality ofdifferent pairs of said fixed contact points when the mobile contactassembly is moved in the opposite direction, and an actuator assemblymovably supported on said cup-shaped actuator support shell and engagingsaid mobile Contact assembly to effect movement thereof in a selecteddirection.

2. The combination according to claim 1, in which a ground shell ismounted on the bottom of said fixed-contact support shell in concentricalignment with the side wall lthereof whereby movement of said mobilecontact assembly in one direction effects engagement of one pair of saidresilient contact blades with said ground shell while another pair ofsaid resilient contact blades conductively c-onnects two pairs of saidfixed contact points.

3. The combination according to claim 1, in which a cup-shaped groundshell having a bottom and a cylindrical side-wall extends transverselyacross the interior of said envelope on the side of said mobile contactassembly opposite said cup-shape fixed-contact support shell wherebymovement of said mobile contact assembly in one direction effectsengagement of one pair of said resilient contact blades with the bottomof said cup-shaped ground shell while another pair of said resilientcontact blades conductively connects two pairs of said fixed contactpoints.

4. The combination according to claim 1, in which said mobile contactassembly comprises a cruciform dielectric support plate, and said pairsof resilient contact blades are fixed in spaced relation on oppositesides of said cruciform dielectric support plate.

5. The combination according to claim 1, in which said actuator assemblyincludes a shaft slidably disposed on said cup-shaped actuator supportshell and extending into the envelope, an expansible metallic bellowshermetically interposed between said shaft and said cup-shaped actuatorsupport shell, and said mobile contact assembly is mounted on the innerend of said shaft within the envelope.

6. The combination according to claim 1, in which a first ground planeis mounted within the envelope on one side of said mobile contactassembly and a second ground plane is mounted within the envelope on theopposite side of said mobile contact assembly whereby movement of themobile contact assembly toward said first ground plane effectsengagement of one pair of resilient contact blades therewith andengagement of another pair of resilient contact blades with two selectedpairs of fixed contact points whereas movement of the -mobile contactassembly toward said second ground plane effects disengagement of saidone pair of resilient contact blades from said first ground plane andengagement thereof with two different pairs of fixed contacts, andeffects disengagement of said other pair of resilient contact bladesfrom said two first mentioned pairs of fixed contacts and engagementthereof with said second ground plane.

7. The combination according to claim 1, in which said fixed contactpoints comprise circumferentially arranged radially inwardly extendingintegral terminations of said plurality of spaced conductors.

8. The combination according to claim 1, in which shield means areprovided supported on the envelope and interposed between the resilientcontact blades of each pair thereof whereby one resilient contact bladeof each pair of such blades is shielded against inductive capacitancefrom the other resilient contact blade of the same pair.

9. The combination according to claim 2, in which said ground shellmounted on said cup-shaped fixed-contact support shell includes atubular portion brazed at one end to said bottom of said support shelland terminates at its other end in an apertured ground plate, theconfiguration of the aperture being such that the portion of the groundplate which remains cooperates with said resilient contact blades tomaintain substantially constant impedance transmission through therelay.

10. The combination according to claim 3, in which the bottom of saidcup-shaped ground shell is centrally apertured, a portion of sai-dactuator assembly extends through said aperture, and the configurationof the aperture is such that the portion of the ground plate whichremains cooperates with said resilient contact blades to maintainsubstantially constant impedance transmission through the relay.

11. The combination according to claim 3, in which the bottom of saidcup-shaped ground shell is centrally apertured, and a plurality ofcircumferentially spaced radially extending shield plates are m-ountedon said bottom of the ground shell and extend through the aperturetherein past said resilient contact blades in a manner to shield oneresilient contact blade of a pair of such blades against inductivecapacitance from the other resilient contact blade of the same pair.

12. The combination according to claim 3, in which said cup-shapedground shell has its bottom brazed adjacent its outer periphery to saidcup-shaped actuator support shell and its side wall extends across theunion of said cup-shaped actuator and fixed-contact support shells toeffect coaxial alignment thereof.

13. The combination according to claim 3, in which said cup-shapedactuator support shell includes a bottom having a at annular portion anda cylindrical portion joined by a conical portion, and said cup-shapedground shell is supported on said annular portion.

14. In a coaxial relay including an evacuated envelope having acup-shaped metallic end wall including a bottom and a side wall, aplurality of dielectric bushings extending through said bottom andhermetically bonded thereto, a conductive center conductor extendingthrough each said bushing and hermetically bonded thereto, each saidconductive center conductor terminating within the er1- velope in afixed contact point, and a metallic ground plate fixed on said bottomand having apertures coaxially associated with each center conductoroutside the envelope.

References Cited UNITED STATES PATENTS 8/1961 Charles 200-153 X 4/1964Orner 200-153 X

1. A COAXIAL CROSS-POINT RELAY COMPRISING AN ENVELOPE INCLUDING A CUP-SHAPED ACTUATOR SUPPORT SHELL AND A CUPSHAPED FIXED-CONTACT SUPPORT SHELL HERMETICALLY UNITED TO THE ACTUATOR SUPPORT SHELL, EACH OF SAID CUP-SHAPED SHELLS HAVING A BOTTOM AND A CYLINDRICAL SIDE WALL, A PLURALITY OF SPACED CONDUCTORS EXTENDING INSULATEDLY AND HERMETICALLY THROUGH THE BOTTOM OF SAID FIXED-CONTACT SUPPORT SHELL AND TERMINATING WITHIN THE ENVELOPE IN A PLURALITY OF SPACED FIXED CONTACT POINTS, A MOBILE CONTACT ASSEMBLY DISPOSED WITHIN THE ENVELOPE AND INCLUDING PAIRS OF RESILIENT CONTACT BLADES ARRANGED TO CONDUCTIVELY CONNECT A PLURALITY OF PAIRS OF SAID FIXED CONTACT POINTS WHEN THE MOBILE CONTACT ASSEMBLY IS MOVED IN ONE DIRECTION AND TO CONDUCTIVELY CONNECT A PLURALITY OF DIFFERENT PAIRS OF SAID FIXED CONTACT POINTS WHEN THE MOBILE CONTACT ASSEMBLY IS MOVED IN THE OPPOSITE DIRECTION, AND AN ACTUATOR ASSEMBLY MOVABLY SUPPORTED ON SAID CUP-SHAPED ACTUATOR SUPPORT SHELL AND ENGAGING SAID MOBILE CONTACT ASSEMBLY TO EFFECT MOVEMENT THEREOF IN A SELECTED DIRECTION. 